Faculty Publications in Food Science and TechnologyCopyright (c) 2017 University of Nebraska - Lincoln All rights reserved.http://digitalcommons.unl.edu/foodsciefacpub
Recent documents in Faculty Publications in Food Science and Technologyen-usThu, 10 Aug 2017 01:39:04 PDT3600Epidemiological investigation of <i>Candida</i> species causing bloodstream infection in pediatric small bowel transplant recipientshttp://digitalcommons.unl.edu/foodsciefacpub/236
http://digitalcommons.unl.edu/foodsciefacpub/236Tue, 08 Aug 2017 09:19:32 PDT
Small bowel transplantation (SBT) can be a life-saving medical procedure. However, these recipients experience high risk of bloodstream infections caused by Candida. This research aims to characterize the SBT recipient gut microbiota over time following transplantation and investigate the epidemiology of candidemia in seven pediatric patients. Candida species from the recipients’ ileum and bloodstream were identified by internal transcribed spacer sequence and distinguished to strain by multilocus sequence typing and randomly amplified polymorphic DNA. Antifungal susceptibility of bloodstream isolates was determined against nine antifungals. Twenty-two ileostomy samples harbored at least one Candida species. Fungemia were caused by Candida parapsilosis, Candida albicans, Candida glabrata, Candida orthopsilosis and Candida pelliculosa. All but three bloodstream isolates showed susceptibility to all the antifungals tested. One C. glabrata isolate showed multidrug resistance to itraconazole, amphotericin B and posaconazole and intermediate resistance to caspofungin. Results are congruent with both endogenous (C. albicans, C. glabrata) and exogenous (C. parapsilosis) infections; results also suggest two patients were infected by the same strain of C. parapsilosis. Continuing to work towards a better understanding of sources of infection—particularly the exogenous sources—would lead to targeted prevention strategies.

Includes supplementary materials.

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Mallory J. Suhr et al.Characterization of the ecological role of genes mediating
acid resistance in <i>Lactobacillus reuteri</i> during colonization
of the gastrointestinal tracthttp://digitalcommons.unl.edu/foodsciefacpub/235
http://digitalcommons.unl.edu/foodsciefacpub/235Wed, 02 Aug 2017 12:36:45 PDT
Rodent-derived strains of Lactobacillus reuteri densely colonize the forestomach of mice and possess several genes whose predicted functions constitute adaptations towards an acidic environment. The objective of this study was to systematically determine which genes of L. reuteri 100-23 contribute to tolerance towards host gastric acid secretion. Genes predicted to be involved in acid resistance were inactivated, and their contribution to survival under acidic conditions was confirmed in model gastric juice. Fitness of five mutants that showed impaired in vitro acid resistance were then compared through competition experiments in ex-germ-free mice that were either treated with omeprazole, a proton-pump inhibitor that suppresses acid secretion in the stomach, or left untreated. This analysis revealed that the urease cluster was the predominant factor in mediating resistance to gastric acid production. Population levels of the mutant, which were substantially decreased in untreated mice, were almost completely restored through omeprazole, demonstrating that urease production in L. reuteri is mainly devoted to overcome gastric acid. The findings provide novel information on the mechanisms by which L. reuteri colonizes its gastric niche and demonstrate that in silico gene predictions and in vitro tests have limitations for predicting the ecological functions of colonization factors in bacterial symbionts.

Includes supplemental table.

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Janina A. Krumbeck et al.The International Scientific Association for Probiotics and Prebiotics (ISAPP) Consensus Statement on the Definition and Scope of Prebioticshttp://digitalcommons.unl.edu/foodsciefacpub/234
http://digitalcommons.unl.edu/foodsciefacpub/234Thu, 22 Jun 2017 14:00:10 PDT
In December 2016, a panel of experts in microbiology, nutrition and clinical research was convened by the International Scientific Association for Probiotics and Prebiotics to review the definition and scope of prebiotics. Consistent with the original embodiment of prebiotics, but aware of the latest scientific and clinical developments, the panel updated the definition of a prebiotic: a substrate that is selectively utilized by host microorganisms conferring a health benefit. This definition expands the concept of prebiotics to possibly include non-carbohydrate substances, applications to body sites other than the gastrointestinal tract, and diverse categories other than food. The requirement for selective microbiota-mediated mechanisms was retained. Beneficial health effects must be documented for a substance to be considered a prebiotic. The consensus definition applies also to prebiotics for use by animals, in which microbiota-focused strategies to maintain health and prevent disease is as relevant as for humans. Ultimately, the goal of this Consensus Statement is to engender appropriate use of the term ‘prebiotic’ by relevant stakeholders so that consistency and clarity can be achieved in research reports, product marketing and regulatory oversight of the category. To this end, we have reviewed several aspects of prebiotic science including its development, health benefits and legislation.
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Glenn R. Gibson et al.A critical assessment of the “sterile womb” and “in utero colonization” hypotheses: Implications for research on the pioneer infant microbiomehttp://digitalcommons.unl.edu/foodsciefacpub/233
http://digitalcommons.unl.edu/foodsciefacpub/233Tue, 20 Jun 2017 11:32:29 PDT
After more than a century of active research, the notion that the human fetal environment is sterile and that the neonate’s microbiome is acquired during and after birth was an accepted dogma. However, recent studies using molecular techniques suggest bacterial communities in the placenta, amniotic fluid, and meconium from healthy pregnancies. These findings have led many scientists to challenge the “sterile womb paradigm” and propose that microbiome acquisition instead begins in utero, an idea that would fundamentally change our understanding of gut microbiota acquisition and its role in human development. In this review, we provide a critical assessment of the evidence supporting these two opposing hypotheses, specifically as it relates to (i) anatomical, immunological, and physiological characteristics of the placenta and fetus; (ii) the research methods currently used to study microbial populations in the intrauterine environment; (iii) the fecal microbiome during the first days of life; and (iv) the generation of axenic animals and humans. Based on this analysis, we argue that the evidence in support of the “in utero colonization hypothesis” is extremely weak as it is founded almost entirely on studies that (i) used molecular approaches with an insufficient detection limit to study “low-biomass” microbial populations, (ii) lacked appropriate controls for contamination, and (iii) failed to provide evidence of bacterial viability. Most importantly, the ability to reliably derive axenic animals via cesarean sections strongly supports sterility of the fetal environment in mammals. We conclude that current scientific evidence does not support the existence of microbiomes within the healthy fetal milieu, which has implications for the development of clinical practices that prevent microbiome perturbations after birth and the establishment of future research priorities.
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Maria Elisa Perez-Muñoz et al.Prebiotics and synbiotics: Dietary strategies for improving gut healthhttp://digitalcommons.unl.edu/foodsciefacpub/232
http://digitalcommons.unl.edu/foodsciefacpub/232Tue, 20 Jun 2017 11:21:44 PDTPurpose of review — A wide range of dietary carbohydrates, including prebiotic food ingredients, fermentable fibers, and milk oligosaccharides, are able to produce significant changes in the intestinal microbiota. These shifts in the microbial community are often characterized by increased levels of bifidobacteria and lactobacilli. More recent studies have revealed that species of Faecalibacterium, Akkermansia, and other less well studied members may also be enriched. We review the implications of these recent studies on future design of prebiotics and synbiotics to promote gastrointestinal health.

Recent findings — Investigations assessing the clinical outcomes associated with dietary modification of the gut microbiota have shown systemic as well as specific health benefits. Both prebiotic oligosaccharides comprised of a linear arrangement of simple sugars, as well as fiber-rich foods containing complex carbohydrates, have been used in these trials. However, individual variability and nonresponding study participants can make the outcome of dietary interventions less predictable. In contrast, synergistic synbiotics containing prebiotics that specifically stimulate a cognate probiotic provide additional options for personalized gut therapies. Summary — This review describes recent research on how prebiotics and fermentable fibers can influence the gut microbiota and result in improvements to human health.

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Janina A. Krumbeck et al.Potential for Development of Tolerance by <i>Penicillium digitatum</i> and <i>Penicillium italicum</i> after Repeated Exposure to Potassium Sorbatehttp://digitalcommons.unl.edu/foodsciefacpub/231
http://digitalcommons.unl.edu/foodsciefacpub/231Thu, 27 Apr 2017 13:08:03 PDT
Two strains of Penicillium digitatum and one strain of Penicillium italicum were exposed to various levels of sorbic acid and potassium sorbate, and the MICs were determined. Selected strains of the molds were then repeatedly exposed to subinhibitory levels of the compounds to determine whether increased tolerance might develop. The MIC of sorbic acid (pH 4.75) to P. digitatum was between 0.02 and 0.025%. The MIC of sorbate (pH 5.5) to two strains of P. digitatum and P. italicum was found to be between 0.06 and 0.08%. Increasing levels of sorbate resulted in increasing growth suppression of the molds. Populations of P. digitatum were tested for increased tolerance to sorbic acid, and none was found. Individual molds that started from the same parent colony were examined for increased tolerance to potassium sorbate. Two P. digitatum strains developed no observable increased tolerance, but P. italicum developed a slight increase in tolerance to sorbate. When spores of P. italicum and P. digitatum were exposed to higher levels of sorbate for prolonged times, the fungicidal or fungistatic activity of the inhibitor was dependent upon pH, length of exposure time, level of sorbate, and the mold strain.
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Lisa L. Schroeder et al.Profile of Polyphenol Compounds of Five Muscadine
Grapes Cultivated in the United States and in Newly
Adapted Locations in Chinahttp://digitalcommons.unl.edu/foodsciefacpub/230
http://digitalcommons.unl.edu/foodsciefacpub/230Mon, 24 Apr 2017 13:17:45 PDT
Polyphenol compositions and concentrations in skins and seeds of five muscadine grapes (cv. “Noble”, “Alachua”, “Carlos”, “Fry”, and “Granny Val”) cultivated in the United States (Tallahassee-Florida, TA-FL) and South China (Nanning-Guangxi, NN-GX and Pu’er-Yunnan, PE-YN) were investigated, using ultra performance liquid chromatography tandem triple quadrupole time-of-flight mass spectrometry (UPLC Triple TOF MS/MS). Fourteen ellagitannins were newly identified in these muscadine grapes. The grapes grown in NN-GX accumulated higher levels of ellagic acid, methyl brevifolin carboxylate, and ellagic acid glucoside in skins, and penta-O-galloyl-glucose in seeds. In PE-YN, more flavonols were detected in skins, and higher contents of flavan-3-ols, ellagic acid, and methyl gallate were identified in seeds. Abundant seed gallic acid and flavonols were found among the grapes grown in TA-FL. Based on principal component analysis (PCA) of 54 evaluation parameters, various cultivars grown in different locations could be grouped together and vice versa for the same cultivar cultivated in different regions. This is the result of the interaction between genotype and environmental conditions, which apparently influences the polyphenol synthesis and accumulation.
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Zheng Wei et al.Optical probing of gastrocnemius in patients with
peripheral artery disease characterizes myopathic
biochemical alterations and correlates with stage of diseasehttp://digitalcommons.unl.edu/foodsciefacpub/229
http://digitalcommons.unl.edu/foodsciefacpub/229Mon, 24 Apr 2017 13:12:17 PDT
Peripheral artery disease (PAD) is a condition caused by atherosclerotic blockages in the arteries supplying the lower limbs and is characterized by ischemia of the leg, progressive myopathy, and increased risk of limb loss. The affected leg muscles undergo significant changes of their biochemistry and metabolism including variations in the levels of many key proteins, lipids, and nucleotides. The mechanisms behind these changes are poorly understood. The objective of this study was to correlate the severity of the PAD disease stage and associated hemodynamic limitation (determined by the ankle brachial index, ABI) in the legs of the patients with alterations in the biochemistry of chronically ischemic leg muscle as determined by ATR-Fourier transform infrared microspectroscopy. Muscle (gastrocnemius) biopsies were collected from 13 subjects including four control patients (ABI≥0.9), five claudicating patients (0.4 ≤ ABI<0.9), and four critical limb ischemia (CLI) patients (ABI<0.4). Slide mounted specimens were analyzed by ATR-Fourier transform infrared micro-spectroscopy. An analysis of variance and a partial least squares regression model were used to identify significant differences in spectral peaks and correlate them with the ABI. The spectra revealed significant differences (P < 0.05) across control, claudicating, and CLI patients in the fingerprint and functional group regions. Infrared microspectroscopic probing of ischemic muscle biopsies demonstrates that PAD produces significant and unique changes to muscle biochemistry in comparison to control specimens. These distinctive biochemical profiles correlate with disease progression and may provide insight and direction for new targets in the diagnosis and therapy of muscle degeneration in PAD.
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Ryan A. Becker et al.The microbiome of uncontacted Amerindianshttp://digitalcommons.unl.edu/foodsciefacpub/228
http://digitalcommons.unl.edu/foodsciefacpub/228Thu, 30 Mar 2017 12:24:07 PDT
Most studies of the human microbiome have focused on westernized people with life-style practices that decrease microbial survival and transmission, or on traditional societies that are currently in transition to westernization. We characterize the fecal, oral, and skin bacterial microbiome and resistome of members of an isolated Yanomami Amerindian village with no documented previous contact with Western people. These Yanomami harbor a microbiome with the highest diversity of bacteria and genetic functions ever reported in a human group. Despite their isolation, presumably for >11,000 years since their ancestors arrived in South America, and no known exposure to antibiotics, they harbor bacteria that carry functional antibiotic resistance (AR) genes, including those that confer resistance to synthetic antibiotics and are syntenic with mobilization elements. These results suggest that westernization significantly affects human microbiome diversity and that functional AR genes appear to be a feature of the human microbiome even in the absence of exposure to commercial antibiotics. AR genes are likely poised for mobilization and enrichment upon exposure to pharmacological levels of antibiotics. Our findings emphasize the need for extensive characterization of the function of the microbiome and resistome in remote nonwesternized populations before globalization of modern practices affects potentially beneficial bacteria harbored in the human body.
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Jose C. Clemente et al.Negative binomial mixed models for
analyzing microbiome count datahttp://digitalcommons.unl.edu/foodsciefacpub/227
http://digitalcommons.unl.edu/foodsciefacpub/227Thu, 30 Mar 2017 12:11:45 PDT
Background: Recent advances in next-generation sequencing (NGS) technology enable researchers to collect a large volume of metagenomic sequencing data. These data provide valuable resources for investigating interactions between the microbiome and host environmental/clinical factors. In addition to the well-known properties of microbiome count measurements, for example, varied total sequence reads across samples, over-dispersion and zero-inflation, microbiome studies usually collect samples with hierarchical structures, which introduce correlation among the samples and thus further complicate the analysis and interpretation of microbiome count data.

Results: In this article, we propose negative binomial mixed models (NBMMs) for detecting the association between the microbiome and host environmental/clinical factors for correlated microbiome count data. Although having not dealt with zero-inflation, the proposed mixed-effects models account for correlation among the samples by incorporating random effects into the commonly used fixed-effects negative binomial model, and can efficiently handle over-dispersion and varying total reads. We have developed a flexible and efficient IWLS (Iterative Weighted Least Squares) algorithm to fit the proposed NBMMs by taking advantage of the standard procedure for fitting the linear mixed models.

Conclusions: We evaluate and demonstrate the proposed method via extensive simulation studies and the application to mouse gut microbiome data. The results show that the proposed method has desirable properties and outperform the previously used methods in terms of both empirical power and Type I error. The method has been incorporated into the freely available R package BhGLM (http://www.ssg.uab.edu/bhglm/ and http://github.com/abbyyan3/BhGLM), providing a useful tool for analyzing microbiome data.

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Xinyan Zhang et al.The Host Microbiome Regulates and Maintains Human Health:
A Primer and Perspective for Non-Microbiologistshttp://digitalcommons.unl.edu/foodsciefacpub/226
http://digitalcommons.unl.edu/foodsciefacpub/226Mon, 20 Mar 2017 08:49:00 PDT
Humans consider themselves discrete autonomous organisms, but recent research is rapidly strengthening the appreciation that associated microorganisms make essential contributions to human health and well being. Each person is inhabited and also surrounded by his/her own signature microbial cloud. A low diversity of microorganisms is associated with a plethora of diseases, including allergy, diabetes, obesity, arthritis, inflammatory bowel diseases, and even neuropsychiatric disorders. Thus, an interaction of microorganisms with the host immune system is required for a healthy body. Exposure to microorganisms from the moment we are born and appropriate microbiome assembly during childhood are essential for establishing an active immune system necessary to prevent disease later in life. Exposure to microorganisms educates the immune system, induces adaptive immunity, and initiates memory B and T cells that are essential to combat various pathogens. The correct microbial-based education of immune cells may be critical in preventing the development of autoimmune diseases and cancer. This review provides a broad overview of the importance of the host microbiome and accumulating knowledge of how it regulates and maintains a healthy human system.
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Sunil Thomas et al.Investigation of bacterial diversity in the feces of cattle fed different dietshttp://digitalcommons.unl.edu/foodsciefacpub/225
http://digitalcommons.unl.edu/foodsciefacpub/225Fri, 10 Mar 2017 11:03:39 PST
The objective of this study is to investigate individual animal variation of bovine fecal microbiota including as affected by diets. Fecal samples were collected from 426 cattle fed 1 of 3 diets typically fed to feedlot cattle: 1) 143 steers fed finishing diet (83% dry-rolled corn, 13% corn silage, and 4% supplement), 2) 147 steers fed late growing diet (66% dry-rolled corn, 26% corn silage, and 8% supplement), and 3) 136 heifers fed early growing diet (70% corn silage and 30% alfalfa haylage). Bacterial 16S rRNA gene amplicons were determined from individual fecal samples using next-generation pyrosequencing technology. A total of 2,149,008 16S rRNA gene sequences from 333 cattle with at least 2,000 sequences were analyzed. Firmicutes and Bacteroidetes were dominant phyla in all fecal samples. At the genus level, Oscillibacter, Turicibacter, Roseburia, Fecalibacterium, Coprococcus, Clostridium, Prevotella, and Succinivibrio were represented by more than 1% of total sequences. However, numerous sequences could not be assigned to a known genus. Dominant unclassified groups were unclassified Ruminococcaceae and unclassified Lachnospiraceae that could be classified to a family but not to a genus. These dominant genera and unclassified groups differed (P < 0.001) with diets. A total of 176,692 operational taxonomic units (OTU) were identified in combination across all the 333 cattle. Only 2,359 OTU were shared across 3 diet groups. UniFrac analysis showed that bacterial communities in cattle feces were greatly affected by dietary differences. This study indicates that the community structure of fecal microbiota in cattle is greatly affected by diet, particularly between forage- and concentrate-based diets.
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M. Kim et al.A systematic review of the effect of thermal processing
on the allergenicity of tree nutshttp://digitalcommons.unl.edu/foodsciefacpub/224
http://digitalcommons.unl.edu/foodsciefacpub/224Tue, 21 Feb 2017 11:15:10 PSTBackground: Allergenicity of foods can be influenced by processing. Tree nuts are an important source of nutrition and increasingly consumed; however, processing methods are quite variable and data are currently lacking on the effects of processing on allergenicity.

Objective: To perform a systematic literature review on the effects of food processing on the allergenicity of tree nuts.

Methods: A systematic literature search of PubMed and Embase databases was performed, with screening of references, related articles and citations. Studies were included if they assessed the allergenicity or immunogenicity of processed nuts.

Results: The search resulted in 32 articles suitable for analysis. Clinical studies indicate that roasting reduces the allergenicity of hazelnut in individuals with a birch pollen allergy and reactivity to raw hazelnut. Thermal processing may reduce the allergenicity of the PR-10 protein in hazelnut and almond in vitro. The majority of the in vitro studies investigating the allergenicity of nonspecific lipid transfer proteins (nsLTPs) and seed storage proteins in hazelnut, almond, cashew nut, Brazil nut, walnut, pecan nut and pistachio nut show heat stability towards different thermal processing methods.

Conclusion: Thermal processing may reduce allergenicity of PR-10 proteins in hazelnut and almond, in contrast to nsLTPs and seed storage proteins. This has important implications for source materials used for IgE testing and food challenges and diet advice.

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L. J. Masthoff et al.Threshold dose for peanut: Risk characterization based upon diagnostic oral
challenge of a series of 286 peanut-allergic individualshttp://digitalcommons.unl.edu/foodsciefacpub/223
http://digitalcommons.unl.edu/foodsciefacpub/223Tue, 21 Feb 2017 11:15:04 PST
Clinical records of 286 consecutive patients reacting positively with objective symptoms to double-blind, placebo-controlled oral peanut challenges at University Hospital, Nancy, France were examined for individual No Observed Adverse Effect Levels (NOAELs) and Lowest Observed Adverse Effect Levels (LOAELs). After fitting to a log-normal probability distribution model, the ED10 and ED05 were 14.4 and 7.3 mg (expressed as whole peanut), respectively, with 95% lower confidence intervals of 10.7 and 5.2 mg, respectively. Compared to results from a previous study where the ED10 was based upon individual peanut thresholds gleaned from 12 publications, a statistically significant difference was observed between the ED50’s, but not the ED10’s of the two probability distribution curves. The Nancy patient group contains more sensitive subjects than the group from the published literature thus contributing to the observed differences. Minimum eliciting dose-distributions for patients with histories of more severe reactions (grade 4 or 5; 40 subjects) did not differ significantly from those of patients with histories of less severe reactions (grades 1–3; 123 subjects). These data and this modeling approach could be used to establish population thresholds for peanut-allergic consumers and thereby provide a sound basis for allergen control measures in the food industry.
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Steve L. Taylor et al.Food processing and allergenicityhttp://digitalcommons.unl.edu/foodsciefacpub/222
http://digitalcommons.unl.edu/foodsciefacpub/222Tue, 21 Feb 2017 11:14:56 PST
Food processing can have many beneficial effects. However, processing may also alter the allergenic properties of food proteins. A wide variety of processing methods is available and their use depends largely on the food to be processed.

In this review the impact of processing (heat and non-heat treatment) on the allergenic potential of proteins, and on the antigenic (IgG-binding) and allergenic (IgE-binding) properties of proteins has been considered. A variety of allergenic foods (peanuts, tree nuts, cows’ milk, hens’ eggs, soy, wheat and mustard) have been reviewed.

The overall conclusion drawn is that processing does not completely abolish the allergenic potential of allergens. Currently, only fermentation and hydrolysis may have potential to reduce allergenicity to such an extent that symptoms will not be elicited, while other methods might be promising but need more data. Literature on the effect of processing on allergenic potential and the ability to induce sensitisation is scarce. This is an important issue since processing may impact on the ability of proteins to cause the acquisition of allergic sensitisation, and the subject should be a focus of future research. Also, there remains a need to develop robust and integrated methods for the risk assessment of food allergenicity.

Objective: We sought to compare native and chemically modified crude peanut extract (CPE) and major peanut allergens Ara h 2 and Ara h 6 in a mediator-release assay based on the rat basophilic leukemia (RBL) cell line transfected with human Fce receptor.

Methods: Native Ara h 2/6 was reduced and alkylated (RA), with or without additional glutaraldehyde treatment (RAGA). CPE was reduced and alkylated. Sera of subjects with peanut allergy (16 males; median age 7 years) were used for overnight RBL-passive sensitization. Cells were stimulated with 0.1 pg/mL to 10 ug/mL of peanut. B-N-acetylhexosaminidase release (NHR) was used as a marker of RBL degranulation, expressed as a percentage of total degranulation caused by Triton X.

Conclusions: Chemical modification of purified native Ara h 2 and Ara h 6 reduced mediator release in an in vitro assay ~ 100-fold, which indicates decreased allergenicity for further development of the alternative candidate for safe peanut immunotherapy.

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Ramon Bencharitiwong et al.Clinical relevance of sensitization to lupine in peanut-sensitized
adultshttp://digitalcommons.unl.edu/foodsciefacpub/220
http://digitalcommons.unl.edu/foodsciefacpub/220Tue, 21 Feb 2017 11:14:44 PSTBackground: The use of lupine in food has been increasing during the last decade and allergic reactions to lupine have been reported, especially in peanut-allergic patients. The frequency and the degree of cross-reactivity to other legumes are not known. The aim of the study was to investigate the frequency of sensitization to lupine, and in addition to pea and soy, and its clinical relevance, in peanutsensitized patients. Furthermore, to determine the eliciting dose (ED) for lupine using double-blind placebo-controlled food challenges (DBPCFC).

Methods: Thirty-nine unselected peanut-sensitized patients were evaluated by skin prick tests (SPT) and ImmunoCAP to lupine, pea, and soy. Clinical reactivity was measured by DBPCFC for lupine, and by history for pea and soy.

Results: Eighty-two percent of the study population was sensitized to lupine, 55% to pea, and 87% to soy. Clinically relevant sensitization to lupine, pea, or soy occurred in 35%, 29%, and 33% respectively of the study population. None of the patients was aware of the use of lupine in food. The lowest ED for lupine, inducing mild subjective symptoms, was 0.5 mg, and the no observed adverse effect level (NOAEL) was 0.1 mg. No predictive factors for lupine allergy were found.

Conclusion: In peanut-sensitized patients, clinically relevant sensitization to either lupine or to pea or soy occurs frequently. The ED for lupine is low (0.5 mg), which is only five fold higher than for peanut. Patients are not aware of lupine allergy and the presence of lupine in food, indicating that education is important to build awareness.

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K. A. B. M. Peeters et al.Digestibility and IgE-Binding of Glycosylated
Codfish Parvalbuminhttp://digitalcommons.unl.edu/foodsciefacpub/219
http://digitalcommons.unl.edu/foodsciefacpub/219Tue, 21 Feb 2017 11:14:38 PST
Food-processing conditions may alter the allergenicity of food proteins by different means. In this study, the effect of the glycosylation as a result of thermal treatment on the digestibility and IgE-binding of codfish parvalbumin is investigated. Native and glycosylated parvalbumins were digested with pepsin at various conditions relevant for the gastrointestinal tract. Intact proteins and peptides were analysed for apparent molecular weight and IgE-binding. Glycosylation did not substantially affect the digestion. Although the peptides resulting from digestion were relatively large (3 and 4 kDa), the IgE-binding was strongly diminished. However, the glycosylated parvalbumin had a strong propensity to form dimers and tetramers, and these multimers bound IgE intensely, suggesting stronger IgE-binding than monomeric parvalbumin. We conclude that glycosylation of codfish parvalbumin does not affect the digestibility of parvalbumin and that the peptides resulting from this digestion show low IgEbinding, regardless of glycosylation. Glycosylation of parvalbumin leads to the formation of higher order structures that are more potent IgE binders than native, monomeric parvalbumin. Therefore, food-processing conditions applied to fish allergen can potentially lead to increased allergenicity, even while the protein’s digestibility is not affected by such processing.
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Harmen H. J. de Jongh et al.Sandwich Enzyme-Linked Immunosorbent Assay for
Detecting Sesame Seed in Foodshttp://digitalcommons.unl.edu/foodsciefacpub/218
http://digitalcommons.unl.edu/foodsciefacpub/218Tue, 21 Feb 2017 11:14:32 PST
Small amounts of sesame can trigger allergic reactions in sesame-allergic patients. Because sesame is a widely used food ingredient, analytical methods are needed to support quality control and food safety programs in the food industry. In this study, polyclonal antibodies against sesame seed proteins were raised, and an enzyme-linked immunosorbent assay (ELISA) was developed for the detection and quantification of sesame seed residue in food. A comparison was made between this ELISA and other assays, particularly focusing on recovery of sesame seed residue from different food matrices. The developed ELISA is sensitive with a lower limit of quantification of 0.5 ppm and shows essentially no cross-reactivity with other foods or food ingredients (92 tested). The ELISA has a good recovery for analyzing sesame-based tahini in peanut butter, outperforming one other test. In a baked bread matrix, the ELISA has a low recovery, while two other assays perform better. We conclude that a sensitive and specific ELISA can be constructed based on polyclonal antibodies, which is suitable for detection of small amounts of sesame seed relevant for highly allergic patients. Furthermore, we conclude that different food products may require different assays to ensure adequate quantification of sesame.
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Stef J. Koppelman et al.The protein structure determines the sensitizing
capacity of Brazil nut 2S albumin (<i>Ber e1</i>) in a rat
food allergy modelhttp://digitalcommons.unl.edu/foodsciefacpub/217
http://digitalcommons.unl.edu/foodsciefacpub/217Tue, 21 Feb 2017 11:14:26 PST
It is not exactly known why certain food proteins are more likely to sensitize. One of the characteristics of most food allergens is that they are stable to the acidic and proteolytic conditions in the digestive tract. This property is thought to be a risk factor in allergic sensitization. The purpose of the present study was to investigate the contribution of the protein structure of 2S albumin (Ber e1), a major allergen from Brazil nut, on the sensitizing capacity in vivo using an oral Brown Norway rat food allergy model. Disulphide bridges of 2S albumin were reduced and alkylated resulting in loss of protein structure and an increased pepsin digestibility in vitro. Both native 2S albumin and reduced/alkylated 2S albumin were administered by daily gavage dosing (0.1 and 1 mg) to Brown Norway rats for 42 days. Intraperitoneal administration was used as a positive control. Sera were analysed by ELISA and passive cutaneous anaphylaxis. Oral exposure to native or reduced/alkylated 2S albumin resulted in specific IgG1 and IgG2a responses whereas only native 2S albumin induced specific IgE in this model, which was confirmed by passive cutaneous anaphylaxis. This study has shown that the disruption of the protein structure of Brazil nut 2S albumin decreased the sensitizing potential in a Brown Norway rat food allergy model, whereas the immunogenicity of 2S albumin remained preserved. This observation may open possibilities for developing immunotherapy for Brazil nut allergy.
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Jolanda H. M. Van Bilsen et al.